Commit: yuku/yuku.github.io@5fe34e4
Rich snippets are now displayed when the URL of a blog post is shared on Twitter or Facebook, in support of Open Graph protocol (OGP) and Twitter Card.
ブログ書いてみたhttps://t.co/Gehy21W69V
— ゆうく (@yuku_t) 2019年1月7日
During development, I implemented it by referring to the documents, and checked it using the debuggers provided by Facebook and Twitter:
The Facebook's spec requires fb:app_id, so I created a new project for this blog on Facebook and registered that ID as fb:app_id. According to the old information on the web, fb:admin was also supported in the past, but now it seems to be unified into fb:app_id.